Mitochondrial DNA Insertions into Nuclei of Brain Cells

 

It has recently been discovered that mitochondria have been inserting bits of mitochondrial DNA into the nuclei of brain cells at unusually high rates. During a study on over 1,200 older adults, it was found that the more mitochondrial insertions an individual had, the younger they died. One of the normal functions of mitochondria is to ship their DNA into the nucleus of the cell to integrate it with the nuclear DNA in a process called numtogenesis. Numtogenesis has been commonly observed in reproductive cells and cancer cells but has never before been observed in brain cells. These insertions were studied on blood cells and brain tissue from the cerebellum and the dorsolateral prefrontal cortex, or DLPFC. What they found is that cells from the DLPFC had an average of 15 times as many insertions as the blood cells and 5 times as many insertions as the cerebellar cells. It was also discovered that mitochondrial insertions increased under certain stressors such as drug treatments or genetic mutations.

 

In my opinion, this is something that definitely needs more attention. I believe this is something necessary to further study. This study seems to suggest that numtogenesis is somehow linked to life span. Since the DLPFC has been known to be affected by many age related and neurodegenerative conditions, the higher rate in mitochondrial insertions in the DLPFC could provide a potential explanation or be linked as a factor. With this knowledge we could potentially develop improved treatments for these conditions.